Big Bob wrote:
That's funny, most AC condensing units don't have
start capacitors. It is usually an option though.
You may be referring to the oil filled "run" cap
that is connected to the start winding. A start
capacitor is going to be of the electrolytic type
along with a mechanical or solid state start relay.

TDD

No ****??
When did they start doing that?


Many years ago. Start capacitors are going to be a
high value electrolytic type in a black Bakelite
case along with a potential relay. You will see it
on commercial refrigeration equipment because the
compressor often has to start under a load. Under
ideal conditions, a home AC or refrigerator comp
is going to have time for the pressures to equalize
after shutdown before the thermostat calls for cold.
Last summer I had to remove the factory hard start
PTC thermistor from our office condensing unit after
it shorted. That particular setup did not use a
separate start capacitor. I replaced it with a "Kick
Start" device consisting of a potential relay and a
large electrolytic capacitor. A start capacitor and
relay costs the manufacturer a few dollars more per
unit and you may not think it's much money until you
realize that manufacturer has to purchase a million
of them. Here's a page that shows what I'm referring
to:

http://www.toad.net/~jsmeenen/boom.html

The guy has a good site with a lot of information.

http://www.toad.net/~jsmeenen/

TDD